. History and uses of limestones and marbles;. Vermont, Gray LUMACHBLLA NeRA. Ahm*tro!«o k Co. LiTa. Boitom. FOSSILS. ig Nerita, a small Gasteropod found in the chalk of northernItaly. A peculiar sponge resembling a cucumber is found ina dense, siliceous limestone of an ash-gray and straw color. Rhizopods.—These animals, called Foraminifera, becausetheir shells are perforated by pores, and important in the for-mation of calcareous rocks, began their existence at the dawnof animal life, and are found in the deposits of modern seas. The genus Orbulina has only one globular cell while the
. History and uses of limestones and marbles;. Vermont, Gray LUMACHBLLA NeRA. Ahm*tro!«o k Co. LiTa. Boitom. FOSSILS. ig Nerita, a small Gasteropod found in the chalk of northernItaly. A peculiar sponge resembling a cucumber is found ina dense, siliceous limestone of an ash-gray and straw color. Rhizopods.—These animals, called Foraminifera, becausetheir shells are perforated by pores, and important in the for-mation of calcareous rocks, began their existence at the dawnof animal life, and are found in the deposits of modern seas. The genus Orbulina has only one globular cell while theNummulite presents a succession of cells or chambers dividedby transverse septa, and varies from a size nearly microscopicto one and one half inches in diameter; the colors are white,shades of brown, red, and bluish. The Fusilina, a univalve allied to the Nummulite, resemblesa grain of wheat, and was abundant in some countries in theCarboniferous age. The fossil Receptaculite has been called aRhizopod, though it resembles a Coral in some of its character-istics
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Keywords: ., bookcentury1800, bookdecade1880, bookpublisherbosto, bookyear1883
